| Patent application number | Description | Published |
|---|
| 20080250774 | REDUCTANT INJECTION CONTROL STRATEGY - A dosing module for a vehicle comprises a base dose module, a dose adjustment module, and a dose determination module. The base dose module generates a base dose signal that corresponds to a mass flow rate of a dosing agent. The dose adjustment module receives an ammonia (NH3) signal and determines a first dose adjustment based upon the NH3 signal. The NH3 signal indicates NH3 measured downstream of a catalyst. The dose determination module generates a dosing signal based upon the base dose signal and the first dose adjustment. | 10-16-2008 |
| 20080250778 | Excess NH3 storage control for SCR catalysts - A method of regulating an amount of NH3 stored in a catalyst of an exhaust after-treatment system includes determining a mass of NH3 into the catalyst based on a dosing rate of a dosing agent that is injected into an exhaust stream upstream of the catalyst and determining a mass of NH3 out of the catalyst. An accumulated mass of NH3 within the catalyst is calculated based on the mass of NH3 into the catalyst and the mass of NH3 out of the catalyst. The dosing rate is regulated based on the accumulated mass of NH3 within the catalyst. | 10-16-2008 |
| 20090056315 | METHOD FOR REDUCING NH3 RELEASE FROM SCR CATALYSTS DURING THERMAL TRANSIENTS - A control system includes a temperature module that determines a temperature of a selective catalytic reduction (SCR) catalyst, a derivative module that determines a derivative of the temperature, and a dosing module that regulates a dosage of a reductant supplied to the SCR catalyst to regulate an engine out NOx level. A control module generates control signals based on the temperature derivative, wherein the control signals regulate an amount of reductant accumulated within the SCR catalyst to reduce reductant release from the SCR catalyst during thermal transients. | 03-05-2009 |
| 20090158715 | REGENERATION SYSTEM AND METHOD FOR EXHAUST AFTERTREATMENT DEVICES - A method and system is disclosed for regenerating a particulate filter, desulfating a lean NOx trap, desulfating or regenerating a hydrocarbon-selective catalytic reduction catalyst, desulfating or regenerating a urea-selective catalytic reduction catalyst, or a combination thereof. | 06-25-2009 |
| 20100043397 | ON BOARD DIAGNOSTIC MONITOR OF NOX CONVERSION EFFICIENCY FOR AFTERTREATMENT DEVICE - A method for indicating a malfunctioning catalyst in a powertrain including an internal combustion engine and an aftertreatment system including an aftertreatment device utilizing a catalyst to convert NOx includes monitoring a NOx content entering the aftertreatment system, monitoring a NOx content exiting the aftertreatment system, determining an actual conversion efficiency based upon the NOx content entering the aftertreatment system and the NOx content exiting the aftertreatment system, monitoring factors affecting conversion efficiency within the aftertreatment device, determining a malfunction conversion efficiency indicative of the malfunctioning catalyst based upon the factors affecting conversion efficiency within the aftertreatment device, and indicating the malfunctioning catalyst based upon comparing the actual conversion efficiency to the malfunction conversion efficiency. | 02-25-2010 |
| 20100043400 | AFTERTREATMENT DEVICE NOX CONVERSION EFFICIENCY DIAGNOSTICS USING ON BOARD ADAPTIVE DIAGNOSTIC ALGORITHM - A powertrain includes an internal combustion engine and an aftertreatment system having an aftertreatment device utilizing a catalyst to convert NOx. A method for indicating a malfunctioning catalyst includes monitoring an actual NOx content exiting the aftertreatment system, monitoring factors affecting conversion efficiency of the aftertreatment device, determining a predicted threshold NOx content exiting the aftertreatment system for an exemplary malfunctioning catalyst based upon the factors affecting conversion efficiency, comparing the actual NOx content exiting the aftertreatment system to the predicted threshold NOx content exiting the aftertreatment system, and indicating a malfunctioning catalyst based upon the comparing. | 02-25-2010 |
| 20100076666 | TEMPERATURE CONTROL SYSTEM AND METHOD FOR PARTICULATE FILTER REGENERATION USING A HYDROCARBON INJECTOR - A control system includes a first module, a fuel determination module, a temperature error correction module, and a hydrocarbon injection control module. The first module determines a temperature difference between a desired inlet temperature of a particulate filter (PF) and an outlet temperature of a first catalyst. The fuel determination module determines an uncorrected desired fuel value based on the temperature difference, an ambient temperature, and a mass flow of exhaust gas. The temperature error correction module generates a desired fuel value based on the uncorrected desired fuel value. The hydrocarbon injection control module controls a hydrocarbon injector based on the desired fuel value. | 03-25-2010 |
| 20100122524 | AMMONIA (NH3) STORAGE CONTROL SYSTEM AND METHOD AT LOW NITROGEN OXIDE (NOx) MASS FLOW RATES - A control system comprising an ammonia (NH | 05-20-2010 |
| 20100132345 | MIXING DEVICES FOR SELECTIVE CATALYTIC REDUCTION SYSTEMS - A selective catalytic reduction (SCR) system includes an exhaust pipe for receiving an exhaust gas from an engine. A selective catalytic reduction (SCR) unit is provided downstream of the exhaust pipe. A first mixing element including a meshed body defines a first surface, a second surface, and a plurality of openings extending from the first surface to the second surface. The first surface and second surface are parallel to each other and define an angle relative to a flow direction of the exhaust flow. The angle is less than 90 degrees. | 06-03-2010 |
| 20100180576 | ROBUST DESIGN OF DIAGNOSTIC ENABLING CONDITIONS FOR SCR NOX CONVERSION EFFICIENCY MONITOR - A method for controlling a malfunction catalyst diagnostic test that determines a malfunction status of a catalyst within a selective catalytic reduction device includes monitoring an exhaust gas flow within an aftertreatment system, estimating an effect of the exhaust gas flow on an estimated reductant storage on a catalyst within the selective catalytic reduction device, and selectively disabling the malfunction catalyst diagnostic test based upon the estimating the effect of the exhaust gas flow on the estimated reductant storage. | 07-22-2010 |
| 20100223908 | AMMONIA (NH3) STORAGE CONTROL SYSTEM AND METHOD BASED ON A NITROGEN OXIDE (NOx) SENSOR - A control system comprising an upstream nitrogen oxide (NO | 09-09-2010 |
| 20110083424 | METHOD AND APPARATUS FOR MONITORING A REDUCTANT INJECTION SYSTEM IN AN EXHAUST AFTERTREATMENT SYSTEM - An internal combustion engine operating at a lean air/fuel ratio includes a reductant injection system configured to dispense reductant into an exhaust gas feedstream upstream of a selective catalytic reduction device. The reductant injection system includes a reductant delivery system fluidly coupled to a reductant dispensing device that is configured to dispense the reductant. A method for monitoring the reductant injection system includes commanding the reductant dispensing device to dispense reductant at a prescribed reductant flowrate, controlling the reductant delivery system to a preferred operating state, monitoring operation of the reductant delivery system and estimating a reductant flowrate as a function of the monitored operation of the reductant delivery system, and diagnosing operation of the reductant injection system as a function of the prescribed reductant flowrate and the estimated reductant flowrate. | 04-14-2011 |
| 20110146243 | EXHAUST GAS AFTERTREATMENT SYSTEM FOR A DIESEL ENGINE AND METHOD OF INCREASING A TEMPERATURE OF AN SCR CATALYST TO REDUCE NOx IN EXHAUST GASES - An exhaust gas aftertreatment system for a diesel engine is provided. The system includes a controller operably coupled to the engine that induces the engine to combust a rich air/fuel mixture in at least one cylinder at a predetermined time interval after startup of the engine to output exhaust gases including elevated levels of CO, and a percentage increase in HC that is less than a minimal threshold percentage relative to combusting a lean air/fuel mixture. The system further includes a diesel oxidation catalyst that receives the exhaust gases and oxidizes the CO to obtain an exothermic reaction that increases a temperature of the exhaust gases flowing through the oxidation catalyst to greater than a threshold temperature level. The system further includes an SCR catalyst which receives the exhaust gases and reduces NO | 06-23-2011 |
